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el hefe
Mar 21, 2008, 05:13 PM
Have a carrier outdoor package unit A/C and electric heat. Recently changed from the carrier programmable to a standard heat/cool stat. original stat had a light that would indicate when the filter needed changed, assume this was the blue wire that we did not connect when installing the new standard stat. r-red, w-heat, g-green fan, y- cool and capped the blue. Unit heats but will not blow in auto mode, fan runs in on mode and also runs properly in auto when in cooling mode... entire system operated correctly prior to changing t stat... any help on what's wrong?

hvac1000
Mar 21, 2008, 05:26 PM
There is a fan control switch located in the outside unit. It could be a thermo disc or a time delay. When the unit heats up outside this part tells the unit to turn on the blower. Post model of thermostat and the brand name and I will check on the thermostat possibilities.

el hefe
Mar 21, 2008, 06:13 PM
Thank you. We are trying to install a Honeywell CT31 non programmable... the carrier unit outside is a model 50ZP-036---311 with a serial of 1799G42426

el hefe
Mar 21, 2008, 06:17 PM
We have let the unit run in heat mode for up to 3 minutes with no fan response in auto mode, in on mode it blows HOT air... the t-stat instructions stat that if used with an electric furnace set the adj. lever to .3 but of course this made no difference, the fan sill will not operate... we are presently re-installing the original Carrier programmable to see if the unit will still operate properly with the original stat

el hefe
Mar 21, 2008, 06:20 PM
This unit is probably 30 yrs old on a dbl wide in Florida that my father is working on, I'm in Maryland trying to assist him over the phone... Thanks for your help

el hefe
Mar 21, 2008, 06:43 PM
With the original Carrier t-stat now re-installed the unit operates properly in heat and A/C mode... evidently our Honeywell is incompatible... suggestions?

hvac1000
Mar 21, 2008, 08:39 PM
From what I read here

http://customer.honeywell.com/techlit/pdf/69-0000s/69-1809EF.pdf

You might have the wrong stat.

el hefe
Mar 22, 2008, 05:04 AM
Any suggestion on what make/model t-stat will work/ Thanks!

hvac1000
Mar 22, 2008, 05:48 AM
You need one that will work with electric heat.